Passive acoustic box. 20W @ 8 Ohm, 20/10/5W @ L100V. MONITOR 3T MKII consists of a pair of installation speakers that operate in 70/100V and low impedance line applications. It has a switch to select the desired 100 V line power or 8 Ohm impedance. Both devices incorporate a 4" woofer and a 0.5" tweeter. Made of ABS plastic, they have a metal grille and fixing handle included. This model is available in two finishes: white and black.